A Well-Defined Hydrocarbon-Soluble Calcium Hydroxide: Synthesis, Structure, and Reactivity

Controlled hydrolysis of a (β-diketiminate)calcium-amide gave a heteroleptic (β-diketiminate)calcium-hydroxide complex that is remarkably stable against ligand exchange and formation of Ca(OH)2.
The structure of this dimeric complex shows OH- units that symmetrically bridge the Ca2+ ions. This
hydrocarbon-soluble calcium hydroxide reacted rapidly with CO2 to produce a gel from which amorphous
CaCO3 slowly separated. This reaction behavior allows for sol−gel coating with CaCO3 from an organic
solvent. Reaction with benzophenone did not lead to nucleophilic attack of OH- to the carbonyl but gave
a red benzophenone adduct instead.

对(β-二亚胺配体(β-diketiminate))氨基钙进行可控水解，得到一种杂配体型(β-二亚胺配体)氢氧化钙配合物，该配合物对配体交换及氢氧化钙(Ca(OH)₂)的生成过程展现出显著的稳定性。该二聚体配合物的结构显示，其氢氧根(OH⁻)单元可对称桥连钙离子(Ca²⁺)。这种烃溶性氢氧化钙配合物可与二氧化碳(CO₂)快速反应生成凝胶，无定形碳酸钙(amorphous CaCO₃)会缓慢从该凝胶中析出。该反应特性使得可在有机溶剂体系中通过溶胶-凝胶(sol−gel)工艺制备碳酸钙涂层。
该配合物与二苯甲酮(benzophenone)反应时，并未发生氢氧根(OH⁻)对羰基(carbonyl)的亲核进攻(nucleophilic attack)，反而生成了红色二苯甲酮加合物。